package com.yyyyy;

public class Circle {
    private static final double π = 3.14;
    private double radius;

    public Circle(double radius) {
        this.radius = radius;
    }

    public double area() {
        return π * radius * radius;
    }

    public static void main(String[] args) {
        Circle circle = new Circle(10);
        System.out.println("圆的面积是：" + circle.area());
    }
}

